Thursday, July 23, 2009

Matlab: Matrix to a single column

Example:

a=
1 2 3
4 5 6
7 8 9

a=a(:)
->
a=
1
4
7
2
5
8
3
6
9

Matlab: Remove all the unwatned elements in matrix

Today I just got a big set of data, the record of ozone level for one year. When the data is bad or there is no data for a certain point of time , they just use a 999. So I want to remover all of the 999s in this matrix.

If use Excel, that's easy- Find and Replace. In matlab, what I did is this:

Matrix=Matrix(Matrix ~=999)

Here's a simpler example:

a=[1 2 3 4 5 6 7 8 9 ];
b=a(a~=4);
->
b=[1 2 3 5 6 7 8 9]

Wednesday, July 15, 2009

Casio FX4500PA Calculator User Manual Download

I got a Casio fx4500PA calculator several years ago, but I just use it for the simplest calculation. And today I realized that it might be interesting if I do some more complicated job on this calculator. So I found this user manual and it can tell me how to do INTEGRATION and other programming on it. It's pretty cool.

Here's the link to download the user manual:

Casio FX4500PA Calculator User Manual Download

Wednesday, July 1, 2009

Calculate Sequence and Sum

For a(1)=sqrt(2) and a(n+1)=sqrt(2+sqrt(n)), calculate the sequence and sum for n=10.

clc; clear all; close all;

format long;

a=[];


S=[];


a(1)=sqrt(2);


for k=2:11


a(k)=sqrt(2+a(k-1))


end


a=a';


for m=1:k


S(m)=sum(a(1:m));


end



my-alpine and docker-compose.yml

 ``` version: '1' services:     man:       build: .       image: my-alpine:latest   ```  Dockerfile: ``` FROM alpine:latest ENV PYTH...